I never understood why people would want to press the same key twice to get to normal mode. Here's what I use:

  " j + k = normal mode
  inoremap jk <esc>
  inoremap kj <esc>

And yes, it does happen that I want to enter jk or kj and it exits the insert mode. Usually when pasting something and not more often than about once a month. `:set paste!` to the rescue.